The last film you watched....

[Paralus]

Those in the centre were attacked by the line of light infantry ahead of the phalanx - Agriainians and Thracians - showers of javelins were hurled into the elephants and at their drivers.

Not to forget the sarisa. Both Diodorus and Curtius mention this weapon and its advantages explicitly:

Diod. 17.88.1-2
Nevertheless the Macedonians faced the frightening experience manfully. They used their long spears - tais sarisais - to good effect against the Indians stationed beside the elephants, and kept the battle even.

Curtius (8.14.16) adds the salient detail which seems altogether logical:

...they (sarisae) can never serve us better than against these elephants and their drivers...

Whilst it seems logical that the Agrianes and archers (Curtius may well have the "Thracians" mislplaced here they are last attested on satrapal detachment) preceeded the phalanx, Arrian (5.13) explicitly states otherwise:

Near these he placed the royal foot-guard, and next to these the other shield-bearing guards, as each happened at the time to have the right of precedence. On each side, at the extremities of the phalanx, his archers, Agrianians and javelin-throwers were posted.

Arrian has hopelessly confused the royal and regular hypaspists and the the two taxeis of phalanx but the arrangement is clear. Diodorus gives us nothing and Curtius, in near enough terms, reproduces Arrian's "battle plan". Curtius gives the detail that after the phalanx had succeeded in "bursting through the Indian centre in a single charge" Alexander then:

...sent the Agrianes and the Thracian light-armed against the elephants, for they were better at skirmishing than at fighting at close quarters.

Difficult to imagine if the phalanx had already "burst through the Indian centre". Also difficult to do from Arrian's wings.

The "Alexander" movie, of Stone, remains a large disappointment. Conflation of battles and timelines for Hollywood is par for the course but this was something else. My wife bought me the Director's cut DVD and once the silly soliloquy in Babylon begins the stop button is pushed - if not before. Troy was somewhat worse.

Right from left field, I watched the Star Trek film on Saturday. This works and was quite entertaining.

For God's sake Jim, I'm an historian not a fitter and turner!